Wind Turbines By, Matt Macrelli
Basic Facts • A wind turbine is a rotating machine which converts the kinetic energy in wind into mechanical energy. • If the mechanical energy is used directly by machinery, such as a pump or grinding stones, the machine is usually called a windmill. • If the mechanical energy is then converted to electricity, the machine is called a wind generator, wind turbine, wind power unit (WPU), wind energy converter (WEC), or aerogenerator.
Comparison Windmill Wind Turbine
Windmill Use Wind Turbine Use • Grind Wheat to Flower • Grind Corn to Cornmeal • Making Oil • Pumping Water • ELECTRICITY
Size and Power Ratings • The largest machine has blades that span more than the length of a football field, stands 20 building stories high, and produces enough electricity to power 1,400 homes. • A small home-sized wind machine has rotors between 8 and 25 feet in diameter and stands upwards of 30 feet and can supply the power needs of an all-electric home or small business.
Example Prices • A small turbine can cost anywhere from $6,000 to $22,000 installed, depending upon size, application and service agreements with the manufacturer. • Homes use approximately 9,400 kilowatt-hours (kWh) of electricity per year (about 780 kWh per month). Depending upon the average wind speed in the area, a wind turbine rated in the range of 5 to 15 kilowatts would be required to make a significant contribution to meet this demand.